Add counts to Dashboard (#2)

Also refactored database parameters with a few extension methods; ready for profile view page

src/JobsJobsJobs/Client/JobsJobsJobs.Client.csproj

@@ -6,6 +6,7 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="Blazored.Toast" Version="3.1.2" />
     <PackageReference Include="Microsoft.AspNetCore.Components.WebAssembly" Version="5.0.1" />
     <PackageReference Include="Microsoft.AspNetCore.Components.WebAssembly.DevServer" Version="5.0.1" PrivateAssets="all" />
     <PackageReference Include="Microsoft.AspNetCore.WebUtilities" Version="2.2.0" />

src/JobsJobsJobs/Client/Pages/Citizen/Dashboard.razor

@@ -1,47 +1,41 @@
 @page "/citizen/dashboard"
-@inject HttpClient http
-@inject AppState state
 
-<h3>Welcome, @state.User!.Name!</h3>
+<h3>Welcome, @State.User!.Name!</h3>
 
-@if (retrievingProfile)
+@if (RetrievingData)
 {
   <p>Retrieving your employment profile...</p>
 }
-else if (profile != null)
-{
-  <p>Your employment profile was last updated @profile.LastUpdatedOn</p>
-}
 else
 {
-  <p>You do not have an employment profile established; click &ldquo;Profile&rdquo;* in the menu to get started!</p>
-  <p><em>* Once it's there...</em></p>
-}
-
-@if (errorMessage != null)
-{
-  <p>@errorMessage</p>
-}
-@code {
-
-    bool retrievingProfile = true;
-    Profile? profile = null;
-    string? errorMessage = null;
-
-    protected override async Task OnInitializedAsync()
+  if (Profile != null)
+  {
+    <p>
+      Your employment profile was last updated <FullDateTime TheDate="@Profile.LastUpdatedOn" />. Your profile currently
+      lists @SkillCount skill@(SkillCount != 1 ? "s" : "").
+    </p>
+  }
+  else
+  {
+    <p>You do not have an employment profile established; click &ldquo;Profile&rdquo;* in the menu to get started!</p>
+  }
+  <p>
+    There @(ProfileCount == 1 ? "is" : "are") @(ProfileCount == 0 ? "no" : ProfileCount) employment
+    profile@(ProfileCount != 1 ? "s" : "") from citizens of Gitmo Nation.
+    @if (ProfileCount > 0)
     {
-      if (state.User != null)
-      {
-        var profileResult = await ServerApi.RetrieveProfile(http, state);
-        if (profileResult.IsOk)
-        {
-          profile = profileResult.Ok;
-        }
-        else
-        {
-          errorMessage = profileResult.Error;
-        }
-        retrievingProfile = false;
-      }
+      <text>Take a look around and see if you can help them find work!</text>
     }
+  </p>
+}
+
+@if (ErrorMessages.Count > 0)
+{
+  <p><strong>The following error(s) occurred:</strong></p>
+  <p>
+    @foreach (var msg in ErrorMessages)
+    {
+      @msg<br>
+    }
+  </p>
 }

src/JobsJobsJobs/Client/Pages/Citizen/Dashboard.razor.cs

@@ -0,0 +1,96 @@
+using JobsJobsJobs.Shared;
+using JobsJobsJobs.Shared.Api;
+using Microsoft.AspNetCore.Components;
+using System.Collections.Generic;
+using System.Net.Http;
+using System.Threading.Tasks;
+
+namespace JobsJobsJobs.Client.Pages.Citizen
+{
+    /// <summary>
+    /// The first page a user sees after signing in
+    /// </summary>
+    public partial class Dashboard : ComponentBase
+    {
+        /// <summary>
+        /// Whether the data is being retrieved
+        /// </summary>
+        private bool RetrievingData { get; set; } = true;
+
+        /// <summary>
+        /// The user's profile
+        /// </summary>
+        private Profile? Profile { get; set; } = null;
+
+        /// <summary>
+        /// The number of skills in the user's profile
+        /// </summary>
+        private long SkillCount { get; set; } = 0L;
+
+        /// <summary>
+        /// The number of profiles
+        /// </summary>
+        private long ProfileCount { get; set; } = 0L;
+
+        /// <summary>
+        /// Error messages from data access
+        /// </summary>
+        private IList<string> ErrorMessages { get; } = new List<string>();
+
+        /// <summary>
+        /// The HTTP client to use for API access
+        /// </summary>
+        [Inject]
+        public HttpClient Http { get; set; } = default!;
+
+        /// <summary>
+        /// The current application state
+        /// </summary>
+        [Inject]
+        public AppState State { get; set; } = default!;
+
+
+        protected override async Task OnInitializedAsync()
+        {
+            if (State.User != null)
+            {
+                ServerApi.SetJwt(Http, State);
+                var profileTask = ServerApi.RetrieveProfile(Http, State);
+                var profileCountTask = ServerApi.RetrieveOne<Count>(Http, "profile/count");
+                var skillCountTask = ServerApi.RetrieveOne<Count>(Http, "profile/skill-count");
+
+                await Task.WhenAll(profileTask, profileCountTask, skillCountTask);
+
+                if (profileTask.Result.IsOk)
+                {
+                    Profile = profileTask.Result.Ok;
+                }
+                else
+                {
+                    ErrorMessages.Add(profileTask.Result.Error);
+                }
+
+                if (profileCountTask.Result.IsOk)
+                {
+                    ProfileCount = profileCountTask.Result.Ok?.Value ?? 0;
+                }
+                else
+                {
+                    ErrorMessages.Add(profileCountTask.Result.Error);
+                }
+
+                if (skillCountTask.Result.IsOk)
+                {
+                    SkillCount = skillCountTask.Result.Ok?.Value ?? 0;
+                }
+                else
+                {
+                    ErrorMessages.Add(skillCountTask.Result.Error);
+                }
+
+                RetrievingData = false;
+            }
+        }
+
+    }
+}

src/JobsJobsJobs/Client/Pages/Citizen/EditProfile.razor.cs

@@ -1,4 +1,5 @@
-using JobsJobsJobs.Shared;
+using Blazored.Toast.Services;
+using JobsJobsJobs.Shared;
 using JobsJobsJobs.Shared.Api;
 using Microsoft.AspNetCore.Components;
 using System.Collections.Generic;
@@ -51,6 +52,12 @@ namespace JobsJobsJobs.Client.Pages.Citizen
         [Inject]
         private AppState State { get; set; } = default!;
 
+        /// <summary>
+        /// Toast service
+        /// </summary>
+        [Inject]
+        private IToastService Toasts { get; set; } = default!;
+
         protected override async Task OnInitializedAsync()
         {
             ServerApi.SetJwt(Http, State);
@@ -128,12 +135,13 @@ namespace JobsJobsJobs.Client.Pages.Citizen
             var res = await Http.PostAsJsonAsync("/api/profile/save", ProfileForm);
             if (res.IsSuccessStatusCode)
             {
-                // TODO: success notification
+                Toasts.ShowSuccess("Profile Saved Successfully");
             }
             else
             {
-                // TODO: probably not the best way to handle this...
-                ErrorMessages.Add(await res.Content.ReadAsStringAsync());
+                var error = await res.Content.ReadAsStringAsync();
+                if (!string.IsNullOrEmpty(error)) error = $"- {error}";
+                Toasts.ShowError($"{(int)res.StatusCode} {error}");
             }
         }
 

src/JobsJobsJobs/Client/Program.cs

@@ -1,13 +1,10 @@
+using Blazored.Toast;
 using Microsoft.AspNetCore.Components.WebAssembly.Hosting;
-using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
-using Microsoft.Extensions.Logging;
 using NodaTime;
 using NodaTime.Serialization.SystemTextJson;
 using System;
-using System.Collections.Generic;
 using System.Net.Http;
-using System.Text;
 using System.Text.Json;
 using System.Threading.Tasks;
 
@@ -23,6 +20,7 @@ namespace JobsJobsJobs.Client
             builder.Services.AddScoped(sp => new HttpClient { BaseAddress = new Uri(builder.HostEnvironment.BaseAddress) });
             builder.Services.AddSingleton(new AppState());
             builder.Services.AddSingleton(new JsonSerializerOptions().ConfigureForNodaTime(DateTimeZoneProviders.Tzdb));
+            builder.Services.AddBlazoredToast();
             await builder.Build().RunAsync();
         }
     }

src/JobsJobsJobs/Client/ServerApi.cs

@@ -131,7 +131,7 @@ namespace JobsJobsJobs.Client
         /// </summary>
         /// <typeparam name="T">The type of item expected</typeparam>
         /// <param name="http">The HTTP client to use for server communication</param>
-        /// <param name="url">The API URL to use call</param>
+        /// <param name="url">The API URL to call</param>
         /// <returns>A result with the items, or an error if one occurs</returns>
         /// <remarks>The caller is responsible for setting the JWT on the HTTP client</remarks>
         public static async Task<Result<IEnumerable<T>>> RetrieveMany<T>(HttpClient http, string url)
@@ -150,5 +150,29 @@ namespace JobsJobsJobs.Client
                 return Result<IEnumerable<T>>.AsError($"Unable to parse result: {ex.Message}");
             }
         }
+
+        /// <summary>
+        /// Retrieve one item from the given URL
+        /// </summary>
+        /// <typeparam name="T">The type of item expected</typeparam>
+        /// <param name="http">The HTTP client to use for server communication</param>
+        /// <param name="url">The API URL to call</param>
+        /// <returns>A result with the item (possibly null), or an error if one occurs</returns>
+        /// <remarks>The caller is responsible for setting the JWT on the HTTP client</remarks>
+        public static async Task<Result<T?>> RetrieveOne<T>(HttpClient http, string url)
+        {
+            try
+            {
+                return Result<T?>.AsOk(await http.GetFromJsonAsync<T>($"/api/{url}", _serializerOptions));
+            }
+            catch (HttpRequestException ex)
+            {
+                return Result<T?>.AsError(ex.Message);
+            }
+            catch (JsonException ex)
+            {
+                return Result<T?>.AsError($"Unable to parse result: {ex.Message}");
+            }
+        }
     }
 }

src/JobsJobsJobs/Client/Shared/FullDateTime.razor

@@ -0,0 +1,23 @@
+@using NodaTime
+@using NodaTime.Text
+@using System.Globalization
+
+@Translated
+
+@code {
+    /// <summary>
+    /// The pattern with which dates will be formatted
+    /// </summary>
+    private static InstantPattern pattern = InstantPattern.Create("ld<D> ' at ' lt<t>", CultureInfo.CurrentCulture);
+
+    /// <summary>
+    /// The date to be formatted
+    /// </summary>
+    [Parameter]
+    public Instant TheDate { get; set; }
+
+    /// <summary>
+    /// The formatted date
+    /// </summary>
+    private string Translated => pattern.Format(TheDate);
+}

src/JobsJobsJobs/Client/Shared/MainLayout.razor

@@ -1,5 +1,6 @@
 @inherits LayoutComponentBase
 @inject IJSRuntime js
+@using Blazored.Toast.Configuration
 
 <div class="page">
   <div class="sidebar">
@@ -20,6 +21,8 @@
 
   </div>
 </div>
+<BlazoredToasts Position="ToastPosition.BottomRight"
+                ShowProgressBar="true" />
 
 @code {
     async void PlayJobs() => await js.InvokeVoidAsync("Audio.play", "pelosijobs");

src/JobsJobsJobs/Client/_Imports.razor

@@ -1,4 +1,6 @@
-@using System.Net.Http
+@using Blazored.Toast
+@using Blazored.Toast.Services
+@using System.Net.Http
 @using System.Net.Http.Json
 @using Microsoft.AspNetCore.Components.Forms
 @using Microsoft.AspNetCore.Components.Routing

src/JobsJobsJobs/Client/wwwroot/index.html

@@ -2,13 +2,14 @@
 <html>
 
 <head>
-    <meta charset="utf-8" />
-    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no" />
-    <title>JobsJobsJobs</title>
-    <base href="/" />
-    <link href="css/bootstrap/bootstrap.min.css" rel="stylesheet" />
-    <link href="css/app.css" rel="stylesheet" />
-    <link href="JobsJobsJobs.Client.styles.css" rel="stylesheet" />
+  <meta charset="utf-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no">
+  <title>JobsJobsJobs</title>
+  <base href="/">
+  <link href="css/bootstrap/bootstrap.min.css" rel="stylesheet">
+  <link href="css/app.css" rel="stylesheet">
+  <link href="JobsJobsJobs.Client.styles.css" rel="stylesheet">
+  <link href="_content/Blazored.Toast/blazored-toast.min.css" rel="stylesheet">
 </head>  
 
 <body>

src/JobsJobsJobs/Server/Areas/Api/Controllers/ProfileController.cs

@@ -103,5 +103,19 @@ namespace JobsJobsJobs.Server.Areas.Api.Controllers
             await _db.OpenAsync();
             return Ok(await _db.FindSkillsByCitizen(CurrentCitizenId));
         }
+
+        [HttpGet("count")]
+        public async Task<IActionResult> GetProfileCount()
+        {
+            await _db.OpenAsync();
+            return Ok(new Count(await _db.CountProfiles()));
+        }
+
+        [HttpGet("skill-count")]
+        public async Task<IActionResult> GetSkillCount()
+        {
+            await _db.OpenAsync();
+            return Ok(new Count(await _db.CountSkills(CurrentCitizenId)));
+        }
     }
 }

src/JobsJobsJobs/Server/Data/CitizenExtensions.cs

@@ -1,9 +1,5 @@
 using JobsJobsJobs.Shared;
 using Npgsql;
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Runtime.CompilerServices;
 using System.Threading.Tasks;
 
 namespace JobsJobsJobs.Server.Data
@@ -31,13 +27,11 @@ namespace JobsJobsJobs.Server.Data
         {
             using var cmd = conn.CreateCommand();
             cmd.CommandText = "SELECT * FROM citizen WHERE na_user = @na_user";
-            cmd.Parameters.Add(new NpgsqlParameter("@na_user", naUser));
+            cmd.AddString("na_user", naUser);
 
             using NpgsqlDataReader rdr = await cmd.ExecuteReaderAsync().ConfigureAwait(false);
-            if (await rdr.ReadAsync().ConfigureAwait(false))
-            {
-                return ToCitizen(rdr);
-            }
+            if (await rdr.ReadAsync().ConfigureAwait(false)) return ToCitizen(rdr);
+            
             return null;
         }
 
@@ -54,12 +48,12 @@ namespace JobsJobsJobs.Server.Data
                 ) VALUES(
                     @na_user, @display_name, @profile_url, @joined_on, @last_seen_on, @id
                 )";
-            cmd.Parameters.Add(new NpgsqlParameter("@id", citizen.Id.ToString()));
-            cmd.Parameters.Add(new NpgsqlParameter("@na_user", citizen.NaUser));
-            cmd.Parameters.Add(new NpgsqlParameter("@display_name", citizen.DisplayName));
-            cmd.Parameters.Add(new NpgsqlParameter("@profile_url", citizen.ProfileUrl));
-            cmd.Parameters.Add(new NpgsqlParameter("@joined_on", citizen.JoinedOn));
-            cmd.Parameters.Add(new NpgsqlParameter("@last_seen_on", citizen.LastSeenOn));
+            cmd.AddString("id", citizen.Id);
+            cmd.AddString("na_user", citizen.NaUser);
+            cmd.AddString("display_name", citizen.DisplayName);
+            cmd.AddString("profile_url", citizen.ProfileUrl);
+            cmd.AddInstant("joined_on", citizen.JoinedOn);
+            cmd.AddInstant("last_seen_on", citizen.LastSeenOn);
 
             await cmd.ExecuteNonQueryAsync().ConfigureAwait(false);
         }
@@ -76,9 +70,9 @@ namespace JobsJobsJobs.Server.Data
                      SET display_name = @display_name,
                          last_seen_on = @last_seen_on
                    WHERE id = @id";
-            cmd.Parameters.Add(new NpgsqlParameter("@id", citizen.Id.ToString()));
-            cmd.Parameters.Add(new NpgsqlParameter("@display_name", citizen.DisplayName));
-            cmd.Parameters.Add(new NpgsqlParameter("@last_seen_on", citizen.LastSeenOn));
+            cmd.AddString("id", citizen.Id);
+            cmd.AddString("display_name", citizen.DisplayName);
+            cmd.AddInstant("last_seen_on", citizen.LastSeenOn);
 
             await cmd.ExecuteNonQueryAsync().ConfigureAwait(false);
         }

src/JobsJobsJobs/Server/Data/NpgsqlExtensions.cs

@@ -11,8 +11,10 @@ namespace JobsJobsJobs.Server.Data
     /// <summary>
     /// Extensions to the Npgsql data reader
     /// </summary>
-    public static class NpgsqlDataReaderExtensions
+    public static class NpgsqlExtensions
     {
+        #region Data Reader
+
         /// <summary>
         /// Get a boolean by its name
         /// </summary>
@@ -48,5 +50,44 @@ namespace JobsJobsJobs.Server.Data
         /// <param name="name">The name of the column to check</param>
         /// <returns>True if the column is null, false if not</returns>
         public static bool IsDBNull(this NpgsqlDataReader rdr, string name) => rdr.IsDBNull(rdr.GetOrdinal(name));
+
+        #endregion
+
+        #region Command
+
+        /// <summary>
+        /// Add a string parameter
+        /// </summary>
+        /// <param name="name">The name of the parameter</param>
+        /// <param name="value">The value of the parameter</param>
+        public static void AddString(this NpgsqlCommand cmd, string name, object value) =>
+            cmd.Parameters.Add(
+                new NpgsqlParameter<string>($"@{name}", value is string @val ? @val : value.ToString()!));
+
+        /// <summary>
+        /// Add a boolean parameter
+        /// </summary>
+        /// <param name="name">The name of the parameter</param>
+        /// <param name="value">The value of the parameter</param>
+        public static void AddBool(this NpgsqlCommand cmd, string name, bool value) =>
+            cmd.Parameters.Add(new NpgsqlParameter<bool>($"@{name}", value));
+
+        /// <summary>
+        /// Add an Instant parameter
+        /// </summary>
+        /// <param name="name">The name of the parameter</param>
+        /// <param name="value">The value of the parameter</param>
+        public static void AddInstant(this NpgsqlCommand cmd, string name, Instant value) =>
+            cmd.Parameters.Add(new NpgsqlParameter<Instant>($"@{name}", value));
+
+        /// <summary>
+        /// Add a parameter that may be null
+        /// </summary>
+        /// <param name="name">The name of the parameter</param>
+        /// <param name="value">The value of the parameter</param>
+        public static void AddMaybeNull(this NpgsqlCommand cmd, string name, object? value) =>
+            cmd.Parameters.Add(new NpgsqlParameter($"@{name}", value == null ? DBNull.Value : value));
+
+        #endregion
     }
 }

src/JobsJobsJobs/Server/Data/ProfileExtensions.cs

@@ -1,6 +1,5 @@
 using JobsJobsJobs.Shared;
 using Npgsql;
-using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
@@ -9,7 +8,7 @@ using System.Threading.Tasks;
 namespace JobsJobsJobs.Server.Data
 {
     /// <summary>
-    /// Extensions to the NpgsqlConnection type to support manipulation of profiles
+    /// Extensions to the Connection type to support manipulation of profiles
     /// </summary>
     public static class ProfileExtensions
     {
@@ -53,7 +52,7 @@ namespace JobsJobsJobs.Server.Data
                     FROM profile p
                         INNER JOIN continent c ON p.continent_id = c.id
                     WHERE citizen_id = @id";
-            cmd.Parameters.Add(new NpgsqlParameter("@id", citizen.Id.ToString()));
+            cmd.AddString("id", citizen.Id);
 
             using var rdr = await cmd.ExecuteReaderAsync().ConfigureAwait(false);
             return await rdr.ReadAsync().ConfigureAwait(false) ? ToProfile(rdr) : null;
@@ -84,17 +83,16 @@ namespace JobsJobsJobs.Server.Data
                         last_updated_on    = @last_updated_on,
                         experience         = @experience
                     WHERE profile.citizen_id = excluded.citizen_id";
-            cmd.Parameters.Add(new NpgsqlParameter("@citizen_id", profile.Id.ToString()));
-            cmd.Parameters.Add(new NpgsqlParameter("@seeking_employment", profile.SeekingEmployment));
-            cmd.Parameters.Add(new NpgsqlParameter("@is_public", profile.IsPublic));
-            cmd.Parameters.Add(new NpgsqlParameter("@continent_id", profile.ContinentId.ToString()));
-            cmd.Parameters.Add(new NpgsqlParameter("@region", profile.Region));
-            cmd.Parameters.Add(new NpgsqlParameter("@remote_work", profile.RemoteWork));
-            cmd.Parameters.Add(new NpgsqlParameter("@full_time", profile.FullTime));
-            cmd.Parameters.Add(new NpgsqlParameter("@biography", profile.Biography.Text));
-            cmd.Parameters.Add(new NpgsqlParameter("@last_updated_on", profile.LastUpdatedOn));
-            cmd.Parameters.Add(new NpgsqlParameter("@experience", 
-                profile.Experience == null ? DBNull.Value : profile.Experience.Text));
+            cmd.AddString("citizen_id", profile.Id);
+            cmd.AddBool("seeking_employment", profile.SeekingEmployment);
+            cmd.AddBool("is_public", profile.IsPublic);
+            cmd.AddString("continent_id", profile.ContinentId);
+            cmd.AddString("region", profile.Region);
+            cmd.AddBool("remote_work", profile.RemoteWork);
+            cmd.AddBool("full_time", profile.FullTime);
+            cmd.AddString("biography", profile.Biography.Text);
+            cmd.AddInstant("last_updated_on", profile.LastUpdatedOn);
+            cmd.AddMaybeNull("experience", profile.Experience);
 
             await cmd.ExecuteNonQueryAsync().ConfigureAwait(false);
         }
@@ -109,7 +107,7 @@ namespace JobsJobsJobs.Server.Data
         {
             using var cmd = conn.CreateCommand();
             cmd.CommandText = "SELECT * FROM skill WHERE citizen_id = @citizen_id";
-            cmd.Parameters.Add(new NpgsqlParameter("citizen_id", citizenId.ToString()));
+            cmd.AddString("citizen_id", citizenId);
 
             var result = new List<Skill>();
             using var rdr = await cmd.ExecuteReaderAsync().ConfigureAwait(false);
@@ -137,10 +135,10 @@ namespace JobsJobsJobs.Server.Data
                     SET skill = @skill,
                         notes = @notes
                     WHERE skill.id = excluded.id";
-            cmd.Parameters.Add(new NpgsqlParameter("id", skill.Id.ToString()));
-            cmd.Parameters.Add(new NpgsqlParameter("citizen_id", skill.CitizenId.ToString()));
-            cmd.Parameters.Add(new NpgsqlParameter("skill", skill.Description));
-            cmd.Parameters.Add(new NpgsqlParameter("notes", skill.Notes == null ? DBNull.Value : skill.Notes));
+            cmd.AddString("id", skill.Id);
+            cmd.AddString("citizen_id", skill.CitizenId);
+            cmd.AddString("skill", skill.Description);
+            cmd.AddMaybeNull("notes", skill.Notes);
 
             await cmd.ExecuteNonQueryAsync().ConfigureAwait(false);
         }
@@ -161,11 +159,39 @@ namespace JobsJobsJobs.Server.Data
                 .Append(string.Join(", ", ids.Select(_ => $"@id{count++}").ToArray()))
                 .Append(')')
                 .ToString();
-            cmd.Parameters.Add(new NpgsqlParameter("citizen_id", citizenId.ToString()));
+            cmd.AddString("citizen_id", citizenId);
             count = 0;
-            foreach (var id in ids) cmd.Parameters.Add(new NpgsqlParameter($"id{count++}", id.ToString()));
+            foreach (var id in ids) cmd.AddString($"id{count++}", id);
 
             await cmd.ExecuteNonQueryAsync().ConfigureAwait(false);
         }
+
+        /// <summary>
+        /// Get a count of the citizens with profiles
+        /// </summary>
+        /// <returns>The number of citizens with profiles</returns>
+        public static async Task<long> CountProfiles(this NpgsqlConnection conn)
+        {
+            using var cmd = conn.CreateCommand();
+            cmd.CommandText = "SELECT COUNT(citizen_id) FROM profile";
+
+            var result = await cmd.ExecuteScalarAsync().ConfigureAwait(false);
+            return result == null ? 0L : (long)result;
+        }
+
+        /// <summary>
+        /// Count the skills for the given citizen
+        /// </summary>
+        /// <param name="citizenId">The ID of the citizen whose skills should be counted</param>
+        /// <returns>The count of skills for the given citizen</returns>
+        public static async Task<long> CountSkills(this NpgsqlConnection conn, CitizenId citizenId)
+        {
+            using var cmd = conn.CreateCommand();
+            cmd.CommandText = "SELECT COUNT(id) FROM skill WHERE citizen_id = @citizen_id";
+            cmd.AddString("citizen_id", citizenId);
+
+            var result = await cmd.ExecuteScalarAsync().ConfigureAwait(false);
+            return result == null ? 0L : (long)result;
+        }
     }
 }

src/JobsJobsJobs/Shared/Api/Count.cs

@@ -0,0 +1,7 @@
+namespace JobsJobsJobs.Shared.Api
+{
+    /// <summary>
+    /// A transport mechanism to send counts across the wire via JSON
+    /// </summary>
+    public record Count(long Value);
+}